Extended data

Inequality is a comprehensive and difficult content in junior high school, senior high school and even competitions, and it is often investigated together with other knowledge points such as equations and functions. The general problems are: solving inequalities, proving inequalities, and finding the maximum and minimum values.

The content of the formula is Hn≤Gn≤An≤Qn, that is, the harmonic average does not exceed the geometric average, the geometric average does not exceed the arithmetic average, and the arithmetic average does not exceed the square average.